6397645 has 8 divisors (see below), whose sum is σ = 7693560. Its totient is φ = 5107200.

The previous prime is 6397631. The next prime is 6397649. The reversal of 6397645 is 5467936.

It can be written as a sum of positive squares in 4 ways, for example, as 879844 + 5517801 = 938^2 + 2349^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 6397645 - 2⁹ = 6397133 is a prime.

It is a super-3 number, since 3×6397645³ (a number of 21 digits) contains 333 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 6397598 and 6397607.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6397649) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1941 + ... + 4069.

It is an arithmetic number, because the mean of its divisors is an integer number (961695).

Almost surely, 2^6397645 is an apocalyptic number.

It is an amenable number.

6397645 is a deficient number, since it is larger than the sum of its proper divisors (1295915).

6397645 is a wasteful number, since it uses less digits than its factorization.

6397645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2735.

The product of its digits is 136080, while the sum is 40.

The square root of 6397645 is about 2529.3566375662. The cubic root of 6397645 is about 185.6407777555.

The spelling of 6397645 in words is "six million, three hundred ninety-seven thousand, six hundred forty-five".